PR 11855

* script.cc (Script_options::Script_options): Initialize
	symbol_definitions_ and symbol_references_.
	(Script_options::add_symbol_assignment): Update
	symbol_definitions_ and symbol_references_.
	(Script_options::add_symbol_reference): New function.
	(script_symbol): New function.
	* script.h (class Script_options): Add symbol_definitions_ and
	symbol_references_ fields.
	(Script_options::referenced_const_iterator): New type.
	(Script_options::referenced_begin): New function.
	(Script_options::referenced_end): New function.
	(Script_options::is_referenced): New function.
	(Script_options::any_unreferenced): New function.
	* script-c.h (script_symbol): Declare.
	* yyscript.y (exp): Call script_symbol.
	* symtab.cc: Include "script.h".
	(Symbol_table::gc_mark_undef_symbols): Add layout parameter.
	Change all callers.  Check symbols referenced by scripts.
	(Symbol_table::add_undefined_symbols_from_command_line): Add
	layout parameter.  Change all callers.
	(Symbol_table::do_add_undefined_symbols_from_command_line):
	Likewise.  Break out loop body.  Check symbols referenced by
	scripts.
	(Symbol_table::add_undefined_symbol_from_command_line): New
	function broken out of
	do_add_undefined_symbols_from_command_line.
	* symtab.h (class Symbol_table): Update declarations.
	* archive.cc: Include "layout.h".
	(Archive::should_include_member): Add layout parameter.  Change
	all callers.  Check for symbol mentioned in expression.
	* archive.h (class Archive): Update declaration.
	* object.cc (Sized_relobj::do_should_include_member): Add layout
	parameter.
	* object.h (Object::should_include_member): Add layout parameter.
	Change all callers.
	(Object::do_should_include_member): Add layout parameter.
	(class Sized_relobj): Update declaration.
	* dynobj.cc (Sized_dynobj::do_should_include_member): Add layout
	parameter.
	* dynobj.h (class Sized_dynobj): Update declaration.
	* plugin.cc (Sized_pluginobj::do_should_include_member): Add
	layout parameter.
	* plugin.h (class Sized_pluginobj): Update declaration.

gold/archive.cc

@@ -36,6 +36,7 @@
 #include "readsyms.h"
 #include "symtab.h"
 #include "object.h"
+#include "layout.h"
 #include "archive.h"
 #include "plugin.h"
 
@@ -603,8 +604,9 @@ Archive::read_symbols(off_t off)
 }
 
 Archive::Should_include
-Archive::should_include_member(Symbol_table* symtab, const char* sym_name,
-                               Symbol** symp, std::string* why, char** tmpbufp,
+Archive::should_include_member(Symbol_table* symtab, Layout* layout,
+			       const char* sym_name, Symbol** symp,
+			       std::string* why, char** tmpbufp,
                                size_t* tmpbuflen)
 {
   // In an object file, and therefore in an archive map, an
@@ -648,13 +650,22 @@ Archive::should_include_member(Symbol_table* symtab, const char* sym_name,
   if (sym == NULL)
     {
       // Check whether the symbol was named in a -u option.
-      if (!parameters->options().is_undefined(sym_name))
-	return Archive::SHOULD_INCLUDE_UNKNOWN;
-      else
+      if (parameters->options().is_undefined(sym_name))
         {
           *why = "-u ";
           *why += sym_name;
         }
+      else if (layout->script_options()->is_referenced(sym_name))
+	{
+	  size_t alc = 100 + strlen(sym_name);
+	  char* buf = new char[alc];
+	  snprintf(buf, alc, _("script or expression reference to %s"),
+		   sym_name);
+	  *why = buf;
+	  delete[] buf;
+	}
+      else
+	return Archive::SHOULD_INCLUDE_UNKNOWN;
     }
   else if (!sym->is_undefined())
     return Archive::SHOULD_INCLUDE_NO;
@@ -726,8 +737,8 @@ Archive::add_symbols(Symbol_table* symtab, Layout* layout,
           Symbol* sym;
           std::string why;
           Archive::Should_include t =
-              Archive::should_include_member(symtab, sym_name, &sym, &why,
-                                             &tmpbuf, &tmpbuflen);
+	    Archive::should_include_member(symtab, layout, sym_name, &sym,
+					   &why, &tmpbuf, &tmpbuflen);
 
 	  if (t == Archive::SHOULD_INCLUDE_NO
               || t == Archive::SHOULD_INCLUDE_YES)
@@ -1015,6 +1026,7 @@ Lib_group::add_symbols(Symbol_table* symtab, Layout* layout,
 	      && (member.sd_ == NULL || member.sd_->symbol_names != NULL))
             {
 	      Archive::Should_include t = obj->should_include_member(symtab,
+								     layout,
 								     member.sd_,
 								     &why);